Egg dehydrator



June- 7, 1938. C. MGLEAN l 2,119,594 n EGG DEHYDRATOR Filed Dec. 6',1934 4 sheets-sheet s IN V EN TOR. 6M'

@www y ATTORNEYS.

June 7,1938;

C.M6LEAN EGG DEHYDRATOR Filed Dec. e, 1934l 4 sheets-sheet 4 VENT R ma wATTORNEYS.

Patented June 7.19378v y y A v l UNITED STATES PATENT OFFICE l Y EGGDEHYDRATOB,

Charles McLean, Berkeley, Calif. Application December 6, 1934, SerlalNo.756,312

'a claims. (ci. 15s-'ii e e This invention relates to egg dehydratorsfor the feeding apparatus `illustrated in Fig. 1, showdehydrating ordesiccating eggs or any other ing the details of construction thereof.more or less viscous substance, or any substance Fig. 3 is a plan viewof the feeding apparatus containing moisture. illustrated in Fig. 2.

The machine is of the class which comprises Fig. 4 is a sectional viewof the feeding appa- 5 generally an endless metallic-belt, means forderatus, taken on line IV--IV of Fig. 3. livering the iiuid to be driedto the'belt as it Fig. 5' is an enlarged viewof one end of the travels,means for heating or otherwise causing distributing roller which forms apart of the feeddesiccation of the fluid on the belt, and means for ingapparatus illustrated in Figs. 2, 3, and 4. l

removing the finished product. The efliciency of Fig. 6 is a view inside elevation of the scrap- 10 a machine of this class depends greatlyupon its ing mechanism. ability to operate continuously and uniformlyFig. 'I isa plan'view of thescraping mechanism over an indefinite periodof time. This is parillustrated in Fig. 6.

ticularly true, owing to the practice of operating Fig. 8 is an enlargedview of the mechanism the machine under vacuum to assist in the de-,employed'for maintaining the belt under tension'ls hydration of theproduct. Whenever it is necesand adjusting the tension on the belt tocompen-' sary to cease operation to repair, adjust or clean 'sate forvariations due to uneven expansion and the machine, it is necessary tobreak the vacuum contraction. in the housing which encases the machineand Fig. 9 is a sectional view, takenon the line reestablish the vacuumat a; considerable loss in IX--IX of Fig.' 8.

time and energy. l .v The machine, as illustrated in the drawings,

The metallic beit" employed travels over a pair comprises an elongatedhousing ilsupported on of spaced cylindrical drums, and in the event ofleg members Il which may besuitably secured to uneven distributionl ofheat, which may be caused the iioor as by pins i! and which is insulatedby an uneven layer of fluid on the belt or failure as shown to preventunnecessary-loss of heat. One 25 to remove parts of the dried product,the belt will end of the housing is closed by a door I3, supbecomedistorted. Upon distortion, caused by ported on hinges i4 and providedwith a gasket irregular expansion and contraction, the beit i5 vofrubber or-other suitable gasket'material tends tooverride the edges ofthe drums with the for the purpose .0f foi-miba an air-tight seal. A

result that operation must be discontinued. Caster I3 may be Provided atthe bOttOm 0f the 30V It is, therefore, the object of the present in-091' t0 engage the n01' and Pawn? 'support vention to provide animproved egg dehydratOr ggl'seight or th? door as it is swung Pon itsinwhich the iluid to be dried is uniformly spread upon a drying beltandthoroughly cleaned therewitmn the housing I. an endless metallic beltriod; and to provide means for impartingv heat to the belt uniformlythroughout its entire-width; gg fmxnch ma jmmls n centran f re receivedb bearings 2i and and to provide means for adjusting the drums 22 sothat upon rotation of tige drums as they over rides,'1n event ofdlstorare supported these bearings the may be tion, without'thenecessity 0f breaking the vacaused to travel continuously within thenouso uum in which the machine operates; and toproing, These bearingswhich support the drums vide further novel-featuresA of constructionthat are mounted on an elongated'framewhich is will promoteeflicient,.continuous, uniform operaillustrated as formed of channeliron andl which tion. y is provided with casters 24 which ride on tracksOne form of my invention is exemplified in the 2l supported by' brackets2O to the inner accompanying drawings, to which reference is" wall ofthe housing.`

made in thefoilowing specification. In the speci- The atmosphere .withinthe housing is maincation further objects and advantages of the mined atlow pressure through suitable pump v invention aremade ppalentlmeans(not shown) connected with pipe, suchas 50,

In the drawingsillustrated at 21, communicating lwith' the intc- Fig. 1is a. longitudinal, :vertical section of an lrior .of the housing sothat-"the drying operation egg dehydratorconstructed 'in accordance with1 may take place with as little .heat as necessary my invention. f andwithout danger ofcooking .0r burning the 5 Fig. 2 is en emerged view inside elevation orproduct being dried.

will impart rotation to the other Suitable gauge means, such asillustrated at 2l, may be provided for determining the condition ofvacuum within the housing,'and temperature, registering gauges, such .asillustrated at 29 and 30, are provided forregistering the exacttemperature at various points within the machine.

'Ihe fluid that is to undergo desiccation is delivered through a pipe 3|and nozzles 32 to the feed mechanism, generally indicated at 33, bymeansofwhich it isv evenly distributed upon the belt in a manner to bemore fully described and carried throughoutA substantially the entirelength of the belt in a heated atmosphere of low pressure for a timesufllcient to accomplish the desired desiccation. whereupon it isremoved from the belt by scrapingmechanism, generally indicated at 34,to fallagainst a chute 35, by means of which it is directed into areceptacle il. The receptacle 36 may also be supported on casters 31bearing on rails 38 to facilitate its removal from the housing when the`door is opened.,

In order to impart rotation to the drums which carry the belt, a driveshaft 39,`extending transversely of the housing, projects through onewall thereof, Where it Amay be connected with any suitable source ofpower (not shown). A gear 40 is carried vby this drive shaft and mesheswith a gear 4I lsecured to the drum I 8, so that upon rotation of thedrive shaft this drum will be caused to. rotate and move the belt whichdrum' through frictional contact therewith.

During` the operation of the machine, the'interior. of "the housing maybe illuminated by electric lights, such' as illustrated at 42, and

' the process may be observed through suitable positions..

glass-covered ports, such as illustrated at 43, arranged in the wall ofthe housing at convenient The ,interior of the housing may be heated bysteam, hot'wat'er, electricity, or any vother suitable medium, and theapparatus shown in the.

drawings is designed for the use of steam. The main heating elementcomprises a stationary steam table 44 positioned directly beneath theupper flight of the belt i1. 'I'his table is provided interiorly withopposed bailles which cause a more or less retarded flow of the heatingmedium therethrough. lThe top surface of the table is fiat andpreferably of slightly greater width than the belt which' passes Aoverthe table in direct contact therewith so that the amount of vheatA,transferred to the material on the belt will be`as great as possible.'I'he direct contact' between the steam table and the belt also infsures equal .heating of the belt throughout its width,"as it eliminatesthe possibility of air currents between the belt and table which wouldinterfere with the uniform heating of the belt. A similar table to thatshown at 44 may also be' provided directlyabove the` lower flight oi.'the belt, as illustrated vat 45.`

Steam (from a source 'of supply not shown) is` delivered through a pipe48 which enters the housing horizontally above the belt, dropsvertically downwardly, as at 41, and .again passes rearwardlyandhorizontally parallel to the axes *of the drums i8 and IS. Branch lines48A and 4 5' supply steam to the forward ends of the' steam 'tables 4 4and, which steam passes through the tables lengthwise, discharging atthe opposite ends thereof-'through the. lines 50 .and 5| to enter a maindischarge line 52,/by means of which the steam is carried out of thehousing.

In the event that it'is desired to heat the belt as it passes over thedrums, I have provided means for supplying steam to the interior of thedrums. To accomplish this, the journals 20 of the drums areconcentrically bored to permit pipes-to enter the drums from the main'drums and gathers at the bottom thereof is forced outwardly by thepressure of the incoming steam; and, furthermore, this positioning ofthe outlet opening causes the steam to-circulate and lill the entiredrum rather than to pass directly through the center of the drum.

The steam supply line is provided with a union yconnection 56 and asimilar union 51 is provided in the discharge line. Upon .disconnectionof the unions 56 and 51 theentire unit, including the belt, drums, feedmechanism and scraping mechanism, is free to roll out of the housing vIon the tracks 25. Outside tracks (not shown) may be positioned toreceive the unit. en thus removed from the housing the unit may bethoroughly cleaned with steam under high pressure, or any other suitablecleansing medium,

and the interior ofthe housing is also unobstructed to facilitaterepairing or cleaning.

When the interior of the housing is washed or steam-cleaned, the surplusmoisture may Vbe drawn off at the rear end through a pipe 8 which servesas a drain. As previously stated, the material to be desiccated isdelivered to the belt I1 in fluid or pasty form by means of thefeedmechanism, generally indicated at 33, the construction of which isshown in detail in Figs. 2, 3, and 4. 'I'his feed mechanism comprises abox to which the fluid is delivered through the nozzles 32, consistingof side Walls 59 and a back wall 60 positioned over the belt. The loweredges of the side walls and back wall are providedl with sealing members6I of rubber or other similar material secured to the box by means o1'screws, such as indicated at 62. Across the back wall of the box ananglemember 63 supports downwardly extending brackets 64 Whichcarryrollersl65- underlying the edges of the belt to maintain the box inclose contact therewith. The belt itself forms the bottom ofthe boxandthe front wall thereof consists of a distributing drum 66. 'Ihedistributing drum 66 is rotatable and, therefore,

.can not be securely fastenedto the side walls 'of the box, but aduid-tight seal is produced by cutting the front ends of the side wallsarcuately to fit over the heads of the drum, as shown,`

and byproviding metal plates 61 secured to the inner sides of the endsofthe box and arcuately cutat their forward edges to be received inmilled annular slots 68 in the heads of the' drum, as illustrated inFigs. 2, 3 and 4. The said slots are of substantially the Asame width asthe metal members 61 vand the close fit of these members, together withthe motion due to rotation 'of the drum, prevents the escape of fluid atthese points.-

The distributing drum 66 is mounted for rotation in conventional rollerbearings 69, the housings for these bearings being formed on bearingarms 10, pivotally supported on pins 1| to permit raising and loweringof the drum to vary the thickness of the uid spread upon the belt.Springs 12 normally urge the distributing drum toward the belt, and cams13, xed to a camactuating shaft 14, bear against the bearing arms 10 .tomove them against the tension of the springs 12 and thus vary the spacebetween the drum and the belt. The cam-actuating shaft 14 extendstransversely of the machine and one ofits ends may be squared for thereception of a wrench to'adjust the position of the. cams 13. Thecentral part of thisshaft may also serve to carry a scraper blade 15, asshown in Figs. 2 and 3, for the purpose of cleaning the distributingdrum as it rotates; and the tension on scraper blade may be adjustedthrough a crank arm 18 connected by means of a link 11 to a lever 18 ona rotatable shaft 19 (Figs. 3 and 4).

The belt1 I1 is maintained at a constant level directly beneath thedistributing drum by means of a roller 80 carried for rotation byjournals 8| in bearings 82 at its ends. The roller 80 is'rotated by achain 83 (see Fig. l)` which drives a sprocket 84 xed to the rollershaft, which chain is driven by a sprocket 85 carried bythe main drumI9. The distributing drum is rotated by a gear 86 which meshes with agear 81 secured to the roller shaft to rotate with the roller.

It is desirable to co'ol the surface of the distributing drum in orderto prevent the fluid from drying or coagulating as it contacts thesurface of the drum. To accomplish this I have provided means forcirculating cold water through the drum while the machine is inoperation. said means comprises an inlet tube 88 entering the drumaxially at one end thereof and supplying water torthe interior of thedrum through ports 89, which water, after passing through the interiorof the drum, exits through similar ports 90 and through an outlet tube9| arranged concentricaliy Within the tube 88 and surrounded by asealing gasket 92 to prevent mixture of the incoming and outgoing water.The tubes 88 and 9| are, of course, non-rotatable and preferably will becarried directly outwardly through theV wall of the vacuum` chamber bysuitable conventional connections V(not shown). A rotary springpressedseal 93 is Vprovided. to prevent escape of the cooling water between thesurfaces of the non-rotatable tube 88 and the rotatable head of thedrum.

Upon operation of the machine, the fluid to be desiccated enteringthrough the nozzles 32 is deposited in the 'feed box, preferably afterpassing over a distributing. plate, such as'illustrated at 94, which isprovided with spaced drain lips 95. Due to the heated and partiallyevacuated atmosphere, this fiuid, particularly if it isan egg, tendstowardebulliency and is in a more or less agitated statewithin the feedbox. Upon coming in contact withthe cooled distributing drum, the fluidis restored to a quiet state and as it is carried by the belt from thefeed box under the y distributing' drum, this drum spreads it in anevenlayer, whereupon it is subjected to uniform treatment during itspassage over the heated table and through the atmosphere ofheat and lowpressure. Thel temperature and pressure Within the housing and thespeed' ofv travel of the belt upon which vthe fluid is spread are sor'egulatedtha't the fluid carried by the belt will have been suitablyanduniformly treated in the The their ends.

` screws I I2.

period of time that is required 'for it te traveI from the feedmechanism to the scraper mech-A anism, generally indicated at 34, bymeans of which it is removed'from the belt.

This scraper mechanism is shown in detail in Figs. 6 and '1, andcomprises a plurality of relatively narrow scraper blades 96 positionedside by side. vidual bearing member 91, which bearing members `aresupported for radial adjustment on a tube 98 so that their scrapingedges may rest against the belt, as best shown in Fig. 6.

The bearing members are held against endwise movement on the tube 98 bymeans of a collar 99 secured to one end of said tube and a collarsecured to the opposite end thereof. The tube 98 is mounted for slidingmovement on a rotatable bar |0I which extends transversely of the beltand is journaled in suitable bearings |02. A cylindrical cam |03,provided with a cam groove |04, is secured to the bar IOI, and thecollar 99 is provided with an arm carrying a dog |06 which rides in thesaid cam groove |04. A bracket |01 is providedwith a milled slot |08which receives the lower edge of the arm |05 for sliding movement, thuspreventing rotation of the tube 98. -The outer end of the bar |0| isfittedwith a sprocket |09, which sprocket is engaged and driven by thesame chain 83 which drives the distributing drum 66, as referred toaboveand illustrated in Fig. 1. Upon rotation of the bar |`0I the cam|03 is rotated and through engagement of the arm |05 with the cam groove|04, the tube which supports the scraper blades is caused to oscillatetransversely of the belt. This oscillating movement causes the scrapingedges of the blades to describe a zig-zag path on the belt, and aslicing action is produced which is considerably more effectivein-removing the desiccated product from the belt than is a simplescraping action.

Each blade is provided `with an indi-4 y Each scraper blade is' held incontact with the belt by means of a spring I|0 secured to the scraperbearing by a bolt I|| at its upper end, and fitted withJ an adjustingscrew ||2 at its lower end, which screw bears against the top surface ofthe blade. The tension may be simultaneously increased on all of theblades by means of `a transversely extending rotatable cam bar |I3 whichengages the springs ||0 intermediate The portion of this cam barengaging the springs is formed eccentrically with respect to the axis ofrotation of the bar, so that upon rotation the pressure on the` springsmay be increased or decreased. 'I'he tension of the springs may bevaried individually and independ-f ently of the cam bar by means of theadjusting A plurality of narrowblades, as i1- lustrated, has been foundto be most effective in removing the product from the belt, as whenasingle blade is employed it is `found that slight ir- -regularities inthe surface of the belt or the hardness of the product that is beingremoved will result in incomplete scraping and the building up of hardmasses of the product' which become i overcooked upon ybeing repeatedlysubjected to the drying temperature-.

With the heating means and described above there is little opportunityfor the metal belt to become distorted, due to variation in temperaturethroughout its width. However, in the event of any such distortion Ihave provided means for adjusting the bearings which support the maindrum I9, which means may be feed mechanism operated from the exterior ofthe housing, without the necessity` of breaking the vacuum, to

counteract any tendency of the belt to override the edges of the drums.This means comprises an adjustable tension device which may be apend andprovided withA a head H6 at its opposite end. A compression spring |I1is interposed between the head IIS and the saddle |I4, and as theopposite end ofthe bar ||5 is anchored to the frame, this spring exertsa force which tends to tighten the belt at all times. By varying thepressure on the spring III of one bearing, the entire drum may be thrownslightly out of line to counteract the tendency of the belt to ride offin the event of any unevenness caused by temperature variations. Thethreaded end of the bar H5 is-anchored to the channel by a bearingmember I'I'I secured thereto by bolts, as shown. This bearing membercarries foi'- rotation an elongated nut ||9 threaded on the bar andprovided at one of its ends with a bevel gear |20. The bevel gear |20 isin mesh with a second bevel gear |2| having an integrally formedtrunnion supported in a bearing |22 carried by a bracket |23. Thistrunnion may be provided with a squared hole at its end for thereception of the squared end of a crank-shaft |24 extending outwardlythrough the wall of the housing through a conventional stumng-box|25,.and tted at its outer end with a hand crank |28. Upon rotation ofthis crank the bevel gear |2|, at -its inner end, rotates the bevel gearon the nut H9, thereby lfeeding the rod ||5 in either direction toincrease or decrease the pressure on the spring 1, as desired. In orderto permit vthis adjustment of the drum, the steam discharge line 54,illustrated in Fig. 1, is preferably made of rubber or other lflexiblematerial, so that the otherwise rigid pipe connections will not bebroken due to movement of the drum.

When it is desired to remove the entire unit from the housing-forcleaning, the crank shaft |24 may be pulled outwardly through itsstuifing box for a distance sufficient to remove its squared end fromthe socket in the bevel gear I2 I.

-While I have shown and described a speciilc form of my invention, itis, of course, to be understood that various changes may be resorted toin the arrangement and construction of its several parts within thespirit and scope of the appended claims.

Having described my invention, what 1. In combination with a belt forconveying iiuid matter to be dried, means for delivering such matter tothe b elt, a box-like structure overlying the belt at the point ofdelivery of matter thereto, means forming 'a seal between the loweredges of the box-like structure and the belt to conne the matter to thebelt, a rotatable drum forming one wall of vsaid box-like structure toevenly distribute the matter over the surface of the belt, said drumhaving annular grooves adjacent its ends, and means on the box-likestructure iltting within said grooves to form a fluidtight joint withthe drum.

2. In combination witha belt for conveying fluid matter to be dried,means for delivering such matter to the belt, abox-like structureoverlying the belt at the point of delivery of matter thereto, arotatable drum forming one wall of said boxlike structure to evenlydistribute the matter over the surface of the belt, said drum havingannular grooves adjacent its ends, and means on the boxlike structuretting within said grooves to form a fluid-tight joint with the drum.

3. In combination, a belt for conveying iluid matter to be dried, meansfor delivering said matterto the belt, a rotatable roller spaced fromthe 1 claim,

belt and positioned adjacent the delivery means for causing evendistribution of the matter over the surface of the belt, and means foradjusting the spacing between the roller and the belt.

CHARLES MCLEAN.

